Electrical receptacle



' Feb. 22,1927;-

' E. F. MARTH ELECTRICAL RECEPTACLE Original Filed May 21, 1933 Patented Feb; 22, 1927.

UNITED STATES 1". EARTH, O18 BROOKLYN, NEW YORK.

ELECTRICAL BECEPTACLE.

Application filed Kay 21, 1928, Serial No. 640,509. Renewed January 12, 1927.

This invention relates to electrical receptacles and has for its primary object the provision of a device of this character 1ncluding a socket member and co-actmg plug,

the latter serving when in its applied relation to the socket to close the circuit in which'the device is arranged and to secure the plug against accidental disengagement from the socket while the device is m use.

Heretofore receptacles of this character have been provided with respective contact devices, certain of which are carried by the plug and others by the socket. These contact devices, due to the construction and arrangement of the receptacle have been the frequent cause of short circuits, due to initial improper engagement of the co-acting contacts which result in the formation of an arc and a burningout ofthe circuit.

' An important object of my invention is to provide a receptacleof this character wherein the contact devices of the plug will be uniformly related to the mating contact devices of the socket, whereby in the act of closingthe circuit by rotating the plug in the socket, the contact devices of the plug will be firmly advanced against the aforesaid mating contact devices of the socket, thereby creating a firm intimate relation to the respective contact devices without creating an arc and at the same time operatively closing the circuit.

Receptacles of this character are used to a large extent in connection with electrical appliances such as sad irons, vacuum cleaners and the like. Where no means are provided for lockin the plug in the socket after the circuit has Ieen closed, pull u on the wires leading to the plug causes dis ocation in the arrangement of the contact devices and sets up an arcing tendency between the contact devices, which in turn, causes short circuits. In my invention I have provided a receptacle which will establish'firm engagement of the respective contact devices with each other and effectively lock said devices in this relation and positively prevent accidental withdrawal of the plug from the socket.

Another object of the invention is to'pro vide a device of this character consisting of mating parts which can be readily connected or disconnected as the occasion necessitates. With these and other objects in view, the invention resides in certain novel construcand 3. These lugs are adapted to receive the 'tion and'combination and arrangement of parts, the essential features of which are hereinafter fully described, are particularly ointed out in the appended claim, and are illustrated in the-acc0mpanying drawing, in to ure 2. g J p Figure 4 is a section on line H ofFigure 2. a

Figure 5 is a perspective view of the guide member. In carrying the invention into e(practice, I. use a socket member 10 construct of porcelain or other insulating material and a mat- 'ing plug 11 knurled at 12 and provided with i" metal contact devices 13, 13. These-devices are operatively connected in any suitable well-known manner with the lead wires .14. Between the ends andformed in the outer edges of the contact devices 13 are notches 15.

The receptacle 1.0 is rovided with a central openinglfi in whic a cylindrical guide member 17 is mounted to respectively slide and rotate. This guide memberis providedwith diametrically disposed slots 18,- 18

in; which the contact devices 13-are adaptedto i'. slide. Said member 17 is also provided with arcuate diametrically disposed contact plates 19, 19 and as shown in Figures 3 and 5, these lates extend to the slots 18 so as to come ilrgto1 engagement with the contact devices The receptacle 10 is provided with arouate lugs 20 as clearly shown in Figures 2 notches 15 in the contact devices 13. In order that the ortionsof the contact devices 13 inward y of the notches 15 can be operatively accommodated in the socket, I provide the latter with arcuate recesses 21 and arranged in these recesses are ar'cuate contact springs 22. Each of these springs is firmly secured at 23 to the socket member and connected with one wire 24 of the circuit in which the device is arranged. The free ends of the springs normally yield toward the guide member 17 so as to bear thereagainst.

The guide member 17 is mounted to slide upon a bolt 25 carried by the socket mam her axially thereof and embracing the bolt and operatively bearin against said mem-- .member 17, the notches are operatively aligned with the arcuate lugs and the plug may be then rotated to bring the edges of the contact devices 13 in to firm engagement with the contact springs 22 as shown in Figure 3. As previously stated the free ends of the springs 22 yield against the member 17 and incident thereto it will be seen that on first rotating the guide member 17 the plates 19 thereof will be advanced over the free ends of the springs 22 and thereby establish circuit connections between the wires 14 and 24. As the rotation of the member 17 is continued, the broad outer edges of the devices 13 are brought firmly against the free ends of the springs 22. Due to this organization of parts it will be seen that the engaging relation of the respective contact devices 13 and 22 is governed with such regularity as to cause uniformity of engagement between said devices and in consequence thereof the objectionable arcing and short eircuiting are entirely eliminated. When the plug has been fully inserted in the socket and turned to the position h w in Figure 3 the lugs 20 serve to securely lock the plug against accidental disconnection from this socket and the customary pull which is exerted upon the plug will not cause derangement of the respective contact devices.

While I have described what I deem to be the most desirable embodiment of my invention, it is obvious that many of the details may be varied without in any way departing from the spirit of my invention, and I therefore do not limit myself to the exact details of construction herein set forth nor to anything less than the whole of my invention limited only by the appended claim.

What is claimed as new is A device of the character described comprising a socket member provided with a central opening, a cylindrical guide member mounted for slidable and rotatable movement within the central opening a headed bolt passing through the guide member to limit its slidable movement, a spring surrounding the bolt and having its end convolutions engaging the bottom of the opening and the guide member respectively 1n a manner to normally position the guide member above the top surface of the socket member, arcuate shaped lugs extending inwardlv from the side walls ofthe'central; opening, said socket being provided witharcuate .shaped recesses belowthe lugs, an areuate shaped contact spring secured in each 'recess in a manner whereby one end of each spring yields normally toward the guide member for contacting engagement therewith, a plug, contacts :projecting from the plug and each contact being provided with a notch to recess the lugs, and said, contacts enga ing the arcuate shaped springs as and for t e purpose specified.

In testimony whereof I have aflixed my Si gnature.

I WARD F, MARTH. 

